The invention relates to a fastener retention system for applying an axial retention force in a plastic molded structure, including axially clamping a filter element in a filter housing, and to methods for making same.
It is known in the prior art to insert fasteners in plastic in various ways, including molding the fastener directly into the plastic, welding the fastener into bosses, e.g. by sonic welding or the like, clipping the fastener over molded-in features, snap-in past flexible tabs, etc.
The present invention provides a system and method for retaining fasteners in plastic, and does not require the use of extra parts or complex assembly procedures. The invention allows both low cost standard fasteners and custom fasteners to be assembled into plastic without requiring the use of robots, expensive custom tools, welders, or additional parts. The present invention provides a sturdy, inexpensive part, with minimized content and manufacturing cost.
The invention is particularly useful for a fastener applying an axial compression force holding a filter element between a cover and a base of a filter housing. In the latter application, the invention retains the high durability for pull-out, push-out, and torque-out, that inserted fasteners must maintain to prevent filter failure.